A touch panel or touch screen is applied to various data processing terminals such as a mobile communication terminal or ATM, or displays such as a TV or monitor. In addition, as the touch panel or touch screen is increasingly applied to compact portable electronic devices, the demand for a more compact and lighter touch panel or touch screen is increasing.
During application of a part constituting a touch panel or touch screen, for example, a conductive film, a pressure-sensitive adhesive may be used. Such a pressure-sensitive adhesive is required to maintain optical transparency under severe conditions such as a high temperature or high temperature and high humidity condition. In addition, it is also required to have durability to prevent lift-off or peeling occurring at a pressure-sensitive adhesive interface.
In addition, according to the structure of a touch panel or touch screen, a pressure-sensitive adhesive may be directly attached to a conductive layer such as an indium tin oxide (ITO) layer or a metal mesh layer. In this case, when the pressure-sensitive adhesive stably inhibits a resistance change of the conductive layer, a touch panel or screen may be stably driven for a long time.